How to get if the image texture node material lost image path with python?
This could be useful, I should have found the method that checks the state of the images.

To check if the image in the node are "Purple":

import bpy

    ob = bpy.context.object
    mat=ob.active_material

        for n in mat.node_tree.nodes:
            if n.type=='TEX_IMAGE':
                img=n.image      
        for i in bpy.data.images:
            if i == img:
                print(i.has_data)

    ###if your material are lost/purple return true


This will go directly to material the node, but you can check it directly in bpy.data.images

for i in bpy.data.images:
    if not i.has_data:
        print('Purple/lost image find: ' + i.name)
##print a list with lost image file


So I suppose this is my answer